Matteo Renzi says the UK could become a ‘less great Britain’ if the out campaign wins the referendum.
Photograph: Armando Dadi/Rex/Shutterstock

The Italian prime minister, Matteo Renzi, has made an emotional appeal to the British people not to make “the wrong choice” in the EU referendum on Thursday, saying a decision to leave would exchange “autonomy for isolation, pride for weakness and identity for self-harm”.

As campaigning enters the final stretch, many EU leaders are refraining from pleading publicly with the UK to vote to stay, fearful of making a counterproductive intervention in a bitterly fought contest that looks likely to go down to the wire.

Don’t vote remain for us Europeans – do it for yourselves | Matteo Renzi

“[It] would not be a disaster, a tragedy or the end of the world for you in the UK chose to leave the EU. It would be worse, because it would be the wrong choice,” Renzi wrote, adding that to leave would not be in keeping with Britain’s tradition of refusing to shirk a challenge.

Senior politicians on both sides of the close-fought referendum battle will be criss-crossing Britain in a final, hectic day of campaigning, with the result of the historic vote still too close to call. David Cameron, who will be travelling the country on a battle bus, is expected to appear with senior figures from other parties and from beyond politics, as the Britain Stronger In Europe campaign seeks to underline the breadth of its support from across the ideological spectrum.

Meanwhile, Vote Leave campaigner Boris Johnson, who has staked his future career on backing Brexit, will tour Britain by helicopter, meeting supporters at a series of stops throughout the country – though campaign sources suggested bad weather could yet put a stop to the plan.

The centre-left Italian prime minister, a prominent but not uncritical Europhile, invited Britain to use the strength of a mandate provided by a remain vote to demand a more effective EU, “one that works better, and better recognises the individual character of the markets of its constituent countries?”

The evident anger towards Brussels that has been on display during the referendum campaign can be transformed into a force to change the EU, some of Renzi’s aides believe. He insisted that “the union is a tool – one that can be improved upon – to turn our individual weaknesses into a common strength.” At present, Renzi conceded, the EU simultaneously tries to do too much and too little.

The Italian prime minister, who has had battles with the European commission, said “there is no super state in Brussels, no pedantic grocer who measures cucumbers and lives on arcane and exacting acronyms that obscure reality. Can London really fear this caricature of Brussels?” The British people will not be persuaded to make the choice to remain in the EU by curses, threats or hatred, Renzi said. Instead, he appealed to the British willingness to confront difficulties.

“If there’s one thing the British have never done when faced with a challenge that concerns their future, their very identity, it is to make the wrong choice,” he said. A less great Britain would be the opposite of what those that want an EU exit desire, he suggested. Although Renzi has previously said there will be no chance of an EU return if the UK votes to leave, he stressed that the former must adapt and learn the lessons of the referendum.

The EU is facing huge challenges, Renzi said, and it needs the distinctive UK contribution. On the political front, he wrote, there are various kinds of populism “that aim to break down and corrode the bonds of our communities”.

Renzi suffered a political reverse this weekend when his Democratic party (PD) lost control of Rome and Turin to Beppe Grillo’s populist Five Star Movement. Renzi is pressing constitutional change in Italy that he has said must pass, or he will resign as prime minister.

Ultimately, he said, he does not want the UK to remain in the EU for the sake of its European partners, but for Britain. “Don’t do it for us. We’re just happy to be in the union with you. Do it, rather, for yourselves, for what you stand for: both the history of a nation that has always looked beyond itself, and a future as a platform for innovation and a capacity for transformation which we all envy and admire.”

Renzi’s call for the EU to respond to the fractious referendum campaign by reforming itself was echoed by the German finance minister, Wolfgang Schäuble. He told a conference in Berlin that he hoped that Britain would vote to remain in the bloc, but that whatever the result, “we won’t be able to go on as we have done, otherwise people will say ‘they haven’t understood’.”